RU2300757C2 - Method of calorimetric measurements of energy of hydrogen links in water subjected to magnetic field - Google Patents

Abstract

FIELD: physical chemistry.

SUBSTANCE: method comprises comparing temperature variation when magnetic field is affected during dissolving of salt-probe, e.g. potassium chloride, in activated water with the temperature variation when during dissolving of the salt in a non-activated water.

EFFECT: enhanced reliability and simplified equipment.

2 dwg, 3 tbl

Description

The invention relates to the field of physical chemistry, devoted to the study of the effects of a magnetic field on water and aqueous solutions.

It is known that under the influence of magnetic fields there are changes in the properties of water and aqueous solutions, these effects explain the change in the energy of interaction of water molecules in the liquid state, i.e. change in hydrogen bond energy.

Indirect spectroscopic methods are known for determining these changes when it is not the hydrogen bond itself that is studied, but its effect on the properties of other bonds. Information on the hydrogen bond in such methods is extracted from the characteristics of the O – H stretching and bending vibration bands, which undergo noticeable changes during dimerization. The relative intensity of the bands of monomer and associative molecules, depending on temperature, changing the ratio between the number of monomers and associates, estimates the energy of hydrogen bonds from spectroscopic data [Bakhshiev N.G. Introduction to molecular spectroscopy / N.G. Bakhshiev. - Leningrad: Publishing house of Leningrad State University, 1987. - P.129].

However, the known methods have the following disadvantages, which are the complexity of the equipment and the duration of the experiment.

Of the known technical solutions, the closest in purpose are direct spectroscopic methods, which analyze the spectra formed as a result of the interaction of incident radiation and mutual vibrations of molecules bound by a hydrogen bond. One of the methods is based on the use of special long-wavelength IR spectrometers and spectrometers for Raman scattering with laser excitation (frequency range 100-200 cm ^-1 ) [Drago R. Physical methods in chemistry / R. Drago. - M .: MIR, 1981. - S.213].

The present invention allows to eliminate the disadvantages of the prototype, which are the complexity of the equipment, the duration of the experiment, the ambiguity of the interpretation of the results.

This invention allows to determine the change in the energy of hydrogen bonds by the values of the temperature jump during dissolution of the salt probe in water that has undergone magnetic treatment for a certain time, and in untreated water using the dependence of the change in the energy of hydrogen bonds on the time of magnetic treatment, which is used to construct the energy value spent on changing the energy of hydrogen bonds, calculated on the basis of data on the heat of dissolution of salt in water.

X g of salt is weighed on the balance. Then 50 x ml of distilled water is measured with a measuring cylinder, poured into a glass, which is installed in the calorimeter. After that, the calorimeter is closed with a lid and a Beckman thermometer, a test tube with salt and a stirrer are lowered into a glass through the hole in it, a well-known principle diagram in Fig. 1 (1 - calorimeter; 2 - inner beaker; 3 - Beckman thermometer; 4 - stirrer ; 5 - test tube with the substance; 6 - tripod). After that, turn on the stirrer and every minute (at least five minutes) the Beckman thermometer reads. After five minutes of uniform temperature change, the tube with salt is removed from the calorimeter and through the hole in the lid, the salt is poured into water with continuous stirring. The registration of temperature continues until a newly established continuous uniform temperature variation is detected.

The thermal effect of dissolution can be represented as follows:

where Q is the thermal effect of salt dissolution, J;

K is the constant of the calorimeter, J / K;

t ₂ is the final temperature, K;

t ₁ - initial temperature, K;

[Malakhova A.N. Workshop on physical and colloidal chemistry / A.N. Malakhova. - Minsk: Higher School, 1974. - P.10]. To determine the heat of dissolution of salt in activated water, an experiment is carried out using the same methodology as for non-activated water, with the only difference being that the water undergoes activation, for example, in a magnetic field.

Based on the obtained data on the temperature jump Δt = t ₂ -t ₁ [K], the heat of dissolution of Q [J] salt in the aqueous system is calculated upon activation, assuming that the heat of dissolution of the salt Q ₀ [J] in the deactivated aqueous system corresponds to the reference value ( the heat of dissolution of KCl at 20 ° C in distilled water is 18.4 kJ / mol).

Processing the results of the experiment is as follows. It is assumed that water activation does not lead to a change in the calorimeter constant (neither the mass nor the heat capacity of the components of the calorimetric system change), the calculation of the heat of dissolution of salt in activated water is reduced in accordance with formula (1) to a simple proportion. The calculation of the energy that went into changing a certain number of hydrogen bonds is carried out according to the formula:

where Q _{water. bond} - the energy spent on changing the energy of hydrogen bonds, J;

Q ₀ - thermal effect of dissolution of salt in non-magnetized water, reference value J / mol;

Δt is the temperature jump during dissolution of salt in magnetized water, K;

Δt ₀ - temperature jump during dissolution of salt in non-magnetized water, K;

m is the mass of salt, g;

M is the molecular weight of the salt, g / mol.

A magnetic field acts as a possible activation, KCl is ideally suited as a salt probe, it manifests itself most indifferently and does not affect the activation of distilled water.

Calculation example.

An experiment is conducted to study the dependence of the change in the energy of hydrogen bonds in distilled water on the time of magnetic treatment. The energy spent on changing a certain number of hydrogen bonds is calculated by formula (2) based on data on the heat of dissolution of 2 g of potassium chloride in 100 ml of water exposed to a constant magnetic field B = 0.08 T at 20 ° C.

For the experiment, distilled water and KCl grade H. p. The heat of dissolution of potassium chloride in non-magnetized water Q ₀ is the experimental reference value ΔН ^{20 ° C} = 18.4 kJ / mol. The processed data are presented in tables 1, 2 and 3. According to table 3, a graphical dependence of Fig. 2 is presented (1 - experimental points, 2 - ΔН = 7.8 + 10.7 · 10 ^{-0.0962 · τ} +0.44 Τ, r = 0.991). Magnetization for more than six hours does not lead to a significant decrease in the heat of dissolution in comparison with six hours of magnetic treatment.

The invention allows to determine the energy spent on changing the energy of hydrogen bonds as a result of exposure to a magnetic field.

Table 1
Calorimetric determination of changes in the energy of hydrogen bonds after exposure to water systems of a magnetic field Magnetization time, τ, hour Mass of salt, m, g Temperature jump Δt, K The energy spent on changing the energy of hydrogen bonds, Q _{water. Bond} , J

, ДжThe average energy spent on changing the energy of hydrogen bonds,

, J Standard deviation, J Confidence Interval, J 0 2.00 1.10 - - - - one 2.00 1.10 0 four 12 eleven 1.98 1.06 eighteen 1.99 1,08 9 2.01 1.12 -9 2 2.00 1.05 22 twenty 6 6 2.00 1.06 eighteen 1.98 1,04 27 2.01 1,07 fourteen 3 2.00 1,03 31 31 3 3 1.98 1,02 36 2.00 1,03 31 2.01 1,04 27 four 1.99 1.01 40 37 four four 1.99 1.01 40 2.00 1,02 36 2.01 1,03 32 5 2.00 1.00 45 45 3 3 1.98 0.99 49 1.99 1.00 45 2.00 1.01 40 6 1.98 0.99 49 48 2 2 2.01 1.00 45 2.00 0.99 49 1.98 0.99 49

Claims (1)

The method of calorimetric determination of changes in the energy of hydrogen bonds after exposure to water systems of a magnetic field, characterized in that the determination of changes in the energy of hydrogen bonds is carried out by the values of the temperature jump when dissolving the salt probe in water that has undergone magnetic treatment for a certain time, and in untreated water, using the dependence of the change in the energy of hydrogen bonds on the time of magnetic treatment, to build which use the amount of energy spent on measuring the hydrogen bond energy calculated on the basis of the data on the heat of dissolution of salt in water, according to the formula

where Q _{water. bond} - energy spent on changing the energy of hydrogen bonds, J; Q ₀ - thermal effect of dissolution of salt in non-magnetized water, reference value J / mol; Δt is the temperature jump during dissolution of salt in magnetized water, K; Δt ₀ - temperature jump during dissolution of salt in non-magnetized water, K; m is the mass of salt, g; M is the molecular weight of the salt, g / mol.

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